Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The nacelle includes a rotor assembly coupled to the gearbox and to the generator. The rotor assembly and the gearbox are mounted on a bedplate located within the nacelle. More specifically, in many wind turbines, the gearbox is mounted to the bedplate via one or more torque supports or arms. The one or more rotor blades capture kinetic energy of wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
More specifically, the majority of commercially available wind turbines utilize multi-stage geared drivetrains to connect the turbine blades to electrical generators. The wind turns the turbine blades, which spin a low speed shaft. The low speed shaft is coupled to an input shaft of a gearbox, which has a higher speed output shaft connected to a generator. Thus, the geared drivetrain aims to increase the velocity of the mechanical motion from the wind.
For example, as shown in FIG. 1, a perspective view of a conventional drivetrain 30 is illustrated. As shown, the drivetrain 30 includes a conventional gearbox 32 having include one or more gears and/or gear trains (not shown) to provide speed and/or torque conversions from the rotor to the generator 24. For example, a typical gearbox may include a gear system having one or more outer planet gears revolving about a central or sun gear. The planet gears are typically mounted on a movable arm or carrier which itself may rotate relative to the sun gear. Further, as shown, the gearbox 32 typically also includes a ring gear 34 configured to mesh with the planet gears.
Over time, normal operating loads and forces from the wind act on the wind turbine components described above and can subject the components to various vibrations, deformations, and/or distortions. Thus, the drivetrain 30 of a modern wind turbine is typically mounted to the bedplate 36 with one or more elastic components configured therebetween so as to absorb various forces and vibrations acting on the wind turbine in an effort to prevent damage. For example, as shown in in FIG. 1, the conventional drivetrain 30 typically includes one or more elastic components 33 (e.g. at interface 35) configured between the torque arm 38 of the gearbox 32 and the bedplate 36.
However, conventional wind turbines require very high torque loads to be transferred from the ring gear 34 into the bearing housing 37 before then passing through the bearing housing 37 through the elastic components 33 at interface 35 into the bedplate 36. As such, a bolted joint 39 between the ring gear 34 and bearing housing 37 is highly loaded. In addition, for some modern wind turbines, more compact gearboxes are being utilized to control the costs and weight of larger megawatt wind turbines. These compact gearboxes transmit torque through bolted flanges having shear pins. However, the higher torque-loaded flanges for the same diameter are causing the traditional torque transmission technology to reach its functional limits. Further, the joint 39 between the ring gear 31 and bearing housing 37 for compact gearboxes is more difficult to design than conventional gearboxes.
Thus, improved systems and methods that eliminate the bolted joint 39 between the ring gear 34 and bearing housing 37 so as to pass torque loads directly to a plurality elastomer pins would be welcomed in the art.